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Utah State University

Theses/Dissertations

2009

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Full-Text Articles in Life Sciences

Investigating Methods To Reduce Black Bear (Ursus Americanus) Visitation To Anthropogenic Food Sources: Conditioned Taste Aversion And Food Removal, Kari D. Signor Dec 2009

Investigating Methods To Reduce Black Bear (Ursus Americanus) Visitation To Anthropogenic Food Sources: Conditioned Taste Aversion And Food Removal, Kari D. Signor

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Conflicts between humans and black bears (Ursus americanus) jeopardize the safety of both humans and bears, especially when bears become food-conditioned to anthropogenic food sources in areas such as campgrounds. Interest in using non-lethal techniques, such as aversive conditioning, to manage such conflicts is growing. I conducted a captive experiment at The Wildlife Science Center in Minnesota and two field experiments in the La Sal Mountains, Utah, to investigate the effects of taste aversion conditioning using thiabendazole (TBZ) with a novel flavor cue and food removal on black bear food consumption and visitation to human food sources. In …


Alternative Sampling And Analysis Methods For Digital Soil Mapping In Southwestern Utah, Colby W. Brungard Dec 2009

Alternative Sampling And Analysis Methods For Digital Soil Mapping In Southwestern Utah, Colby W. Brungard

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Digital soil mapping (DSM) relies on quantitative relationships between easily measured environmental covariates and field and laboratory data. We applied innovative sampling and inference techniques to predict the distribution of soil properties, soil attributes, taxonomic classes, and dominant vegetation across a 30,000-ha complex Great Basin landscape in southwestern Utah. This arid rangeland was characterized by rugged topography, diverse vegetation, and intricate geology. Environmental covariates calculated from digital elevation models (DEM) and spectral satellite data were used to represent factors controlling soil development and distribution. We investigated optimal sample size and sampled the environmental covariates using conditioned Latin Hypercube Sampling (cLHS). …


Effects Of Coyote Removal On Pronghorn And Mule Deer Populations In Wyoming, Dylan Earl Brown Dec 2009

Effects Of Coyote Removal On Pronghorn And Mule Deer Populations In Wyoming, Dylan Earl Brown

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

I studied the relationship between coyote (Canis latrans) removal and pronghorn (Antilocapra americana) and mule deer (Odocoileus hemionus) density and fawn:doe ratios in southwest Wyoming and northeast Utah in 2007 and 2008. Coyote removal variables studied included the number of coyotes removed, ground hours worked, total hours worked, coyotes removed/aerial gunning hour, coyotes removed/ground work hour, and coyotes removed/total effort hour. None of the variables explained changes observed in fawn:doe ratios of pronghorn or mule deer. The number of coyotes removed, ground hours worked, total hours worked, and coyotes removed/aerial gunning hour were positively …


Summer Home Range Fidelity In Adult Female Elk (Cervus Elaphus) In Northwestern Colorado, April M. Brough Dec 2009

Summer Home Range Fidelity In Adult Female Elk (Cervus Elaphus) In Northwestern Colorado, April M. Brough

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Understanding the degree of spatial fidelity of individuals within a species increases our ability to manage appropriately. Elk (Cervus elaphus) is a highly managed species in the Intermountain West, but there is little research evaluating summer home range fidelity of individual elk. We evaluated fidelity of 72 adult female elk to individual summer-fall home ranges in the White River study area in northwestern Colorado during two consecutive summers. Based on individual kernel-estimated utilization distributions, we used (1) the Volume of Intersection (VI) statistic and (2) interannual distances between centers of mass to compare summer range overlap and distribution. …


Effects Of Starch Addition On Low Fat Rennet Curd Properties And Their Partitioning Between Curd And Whey, Kelly Marie Larsen Dec 2009

Effects Of Starch Addition On Low Fat Rennet Curd Properties And Their Partitioning Between Curd And Whey, Kelly Marie Larsen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study determined the impact of starches on the properties of low fat rennet curd as measured by microstructural and instrumental analysis. In experiment 1, 17 starches were initially screened for swelling power, impact of curd yield at 5 g/L and 10 g/L in milk, and settling in rennet-induced partially acidified low fat curd.

Starches examined were narrowed down to five in experiment 2; they included: modified waxy corn starch, waxy rice starch, instant tapioca starch, dextrin, and a modified tapioca starch. These starches were added to skim milk to make rennet-induced partially acidified milk gels. Gels were made by …


The Effect Of Irrigation Diversions On The Mountain Whitefish (Prosopium Williamsoni) Population In The Big Lost River, Patrick Allen Kennedy Dec 2009

The Effect Of Irrigation Diversions On The Mountain Whitefish (Prosopium Williamsoni) Population In The Big Lost River, Patrick Allen Kennedy

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Management agencies documented a decline in the mountain whitefish (Prosopium williamsoni) population on the Big Lost River, and unscreened diversions were recognized as a potential factor for this decline. Research suggests the Big Lost River mountain whitefish population is genetically unique, and it has been petitioned for protection under the Endangered Species Act. In 2007, a basin-wide synopsis of diversions was conducted to describe relative entrainment and identify diversions that entrained the most mountain whitefish. This larger scaled synopsis facilitated a more precise assessment of entrainment by a subset of diversions in 2008. In 2008, the volume that …


Herbicide, Salinity, And Flooding Tolerance Of Foxtail Barley (Hordeum Jubatum L.) And Desirable Pasture Grasses, Karl R. Israelsen Dec 2009

Herbicide, Salinity, And Flooding Tolerance Of Foxtail Barley (Hordeum Jubatum L.) And Desirable Pasture Grasses, Karl R. Israelsen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Research trials performed in the greenhouse compared the tolerance and response of Hordeum jubatum and desirable pasture grass species to herbicides, salinity, and flooding. Desirable grass species used in this study included: 'Fawn' tall fescue (Festuca arundinaceae), 'Garrison' creeping foxtail (Alopecurus arundinaceus), 'Palaton' reed canarygrass (Phalaris arundinacea), 'Climax' timothy (Phleum pratense), 'Alkar' tall wheatgrass (Thinopyrum ponticum), 'Potomac' orchardgrass (Dactylis glomerata), and 'Mustang' altai wildrye (Leymus angustus). Tolerance to herbicides, salinity, and flooding varied significantly among grass species. Herbicide tolerance was tested using four herbicides at five …


The Effects Of Social Status And Learning On Captive Coyote (Canis Latrans) Behavior, Lynne Barbara Gilbert-Norton Dec 2009

The Effects Of Social Status And Learning On Captive Coyote (Canis Latrans) Behavior, Lynne Barbara Gilbert-Norton

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Many canids live within hierarchical social systems that could promote differences in learning or in behavior between ranked individuals. Differences in foraging and territorial behavior have been observed between ranked coyotes (Canis latrans), yet effects of learning and social status on coyote behavior are not thoroughly understood. I explored a) coyote response to an artificial scent boundary and whether response differed by status, b) how foraging coyotes tracked temporal resource change, and c) how coyotes find spatially distributed food, and the effect of dominance on foraging behavior. I used male/female pairs of captive coyotes at the National Wildlife Research Center …


Discovering Metabolic Networks Of Bovine Fertilization, Erin Lynn Young Dec 2009

Discovering Metabolic Networks Of Bovine Fertilization, Erin Lynn Young

Undergraduate Honors Capstone Projects

At the time of fertilization, a dramatic change occurs in the oocyte that transforms this cell from a metaphase arrested state into a metabolically active and dynamic state. The view of the flow of biological processes within organisms has recently shifted from that of a linear path to a more complex network. Biological processes are no longer thought of in the simple terms of DNA to RNA, RNA to proteins, and proteins to final activity. It is now known that many biological processes involve interconnected networks and feedback loops in which DNA, RNA, proteins, and metabolites perform specific roles. We …


Ecological Effects Of Genotypic Diversity On Community And Ecosystem Function, Megan K. Kanaga Dec 2009

Ecological Effects Of Genotypic Diversity On Community And Ecosystem Function, Megan K. Kanaga

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Genotypic diversity within populations can have important evolutionary consequences, but the ecological effects of intraspecific genetic variation on community and ecosystem function have only been studied in a few systems. I present the results of a three-year study designed to address the ecological impacts of genotypic diversity in quaking aspen (Populus tremuloides Michx.), using aspen genotypes planted across genotypic diversity levels (monoculture and mixture) and watering treatment levels (well-watered and water-limited). First, I demonstrated that significant variation exists among genotypes for a wide range of growth, morphological and physiological traits, and quantified high heritability and coefficient of genetic variation …


Designing An Instrument Based On Native Fluorescence To Determine Soil Microbial Content At A Mars Analog Site, Heather D. Smith Dec 2009

Designing An Instrument Based On Native Fluorescence To Determine Soil Microbial Content At A Mars Analog Site, Heather D. Smith

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

For this research project we designed an instrument to detect bacteria via biomolecular fluorescence. We introduce the current understanding of astrobiology, our knowledge of life beyond Earth, and the commonality of Earth life as it pertains to the search for life on Mars. We proposed a novel technique for searching for direct evidence of life on the surface of Mars using fluorescence. We use the arid region of the Mojave Desert as an analog of Mars. Results indicate the fluorescence of the biotic component of desert soils is approximately as strong as the fluorescence of the mineral component. Fluorescence laboratory …


Disturbance Ecology And Vegetation Dynamics At Varying Spatial And Temporal Scales In Southern Rocky Mountain Engelmann Spruce Forests, R. Justin Derose Dec 2009

Disturbance Ecology And Vegetation Dynamics At Varying Spatial And Temporal Scales In Southern Rocky Mountain Engelmann Spruce Forests, R. Justin Derose

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

High-severity disturbances are the primary drivers of Engelmann spruce-subalpine fir ecosystems in the southern Rocky Mountain. Recently, an unprecedented, landscape-wide (at least 250 km2) spruce beetle outbreak killed virtually all the Engelmann spruce on the Markagunt Plateau in southwestern Utah, USA. Results from dendroecological analyses suggested the combination of antecedent disturbance history and drought-driven stand development was responsible for creating suitable host conditions prior to the recent outbreak. Multiple and consistent lines of evidence suggested mixed- and high-severity fires shaped the development of the Markagunt Plateau. Subsequent stand development, influenced by species-specific differential tree-ring response to drought, resulted in the …


An Alternative Futures Study For The Uintah Basin: Exploring 2030, Nicholas E. Kenczka May 2009

An Alternative Futures Study For The Uintah Basin: Exploring 2030, Nicholas E. Kenczka

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

The Uinta Basin is located within the Colorado Plateau consisting of various ecosystems ranging from high elevation mountainous regions to sage and juniper woodlands. The basin rests in the northeast corner of Utah with the largest communities being Vernal, Roosevelt, and Duchesne. Other key features include the Flaming Gorge Recreation Area, Green River, and Dinosaur National Monument. The basin historically has been a major region for natural resource extraction, and the population fluctuation has mirrored the "boom" and "bust" cycles of the industry. The Uintah Basin has recently recognized the need for developing a comprehensive plan for identifying the critical …


Alternative Futures 2030: Ogden Valley, Louis Alan Hurst May 2009

Alternative Futures 2030: Ogden Valley, Louis Alan Hurst

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

Ogden Valley is a high mountain community located in the northern Wasatch Mountain Range (Figure 1), and is located entirely within Weber County, Utah. Three communities sit within the valley: Huntsville, Eden, and Liberty. Early Mormon settlers established these communities in the mid-1800s; however, only the town of Huntsville is incorporated. The rural valley is in close proximity to the densely populated Wasatch Front, in particular, Ogden City. Ogden Valley is approximately 331 square miles and has an elevation that ranges between 4400 and 9700 feet. This wide range in elevation provides a diverse environment for humans, wildlife , and …


Punta Toro Virus Infection In Mice: Strain Differences In Pathogenesis And Regulation Of Interferon Response Pathways, Michelle Mendenhall May 2009

Punta Toro Virus Infection In Mice: Strain Differences In Pathogenesis And Regulation Of Interferon Response Pathways, Michelle Mendenhall

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Adames strain of Punta Toro virus (PTV-A) causes acute hepatic disease in hamsters and mice similar to that seen in natural Rift Valley fever virus (RVFV) infection, while the Balliet strain (PTV-B) is apathogenic. The ability of PTV-A to suppress the interferon (IFN) response has been demonstrated in hamsters and is thought to be a contributing factor to PTV-A's pathogenicity in hamsters. PTV-B is not assumed to exhibit this IFN-antagonistic activity, as it stimulates production of significantly higher IFN-β levels. To elucidate the role of IFN in resistance of mice to PTV-B infection, we utilized mice deficient in a …


The Effectiveness Of The Teens Reaching Youth 4-H Model In A Childhood Nutrition And Physical Activity Education Program, Kristen Rae Stokes Strong May 2009

The Effectiveness Of The Teens Reaching Youth 4-H Model In A Childhood Nutrition And Physical Activity Education Program, Kristen Rae Stokes Strong

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Childhood obesity rates are on the rise. There are detrimental physical and psychological health effects associated with childhood obesity. Society needs proven methods of delivering nutrition and physical activity education to children. The Teens Reaching Youth (TRY) 4-H model has been shown to be effective at delivering curriculum in a variety of topics. To assess the effectiveness of the TRY 4-H model at delivering nutrition and physical activity education to youth, grades third through sixth. The program's objectives were to increase youth participants' nutritional knowledge, improve youth participants' eating and fitness habits, and improve leadership and life skills of the …


Maintaining Population Persistence In The Face Of An Extremely Altered Hydrograph: Implications For Three Sensitive Fishes In A Tributary Of The Green River, Utah, Jared L. Bottcher May 2009

Maintaining Population Persistence In The Face Of An Extremely Altered Hydrograph: Implications For Three Sensitive Fishes In A Tributary Of The Green River, Utah, Jared L. Bottcher

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The ability of an organism to disperse to suitable habitats, especially in modified and fragmented systems, determines individual fitness and overall population viability. The bluehead sucker (Catostomus discobolus), flannelmouth sucker (Catostomus latipinnis), and roundtail chub (Gila robusta) are three species native to the upper Colorado River Basin that now occupy only 50% of their historic range. Despite these distributional declines, populations of all three species are present in the San Rafael River, a highly regulated tributary of the Green River, Utah, providing an opportunity for research. Our goal was to determine the timing and …


River Network Structure: A Template For Understanding Predator-Prey Dynamics And Potential Anthropogenic Impacts, Catherine L. Hein May 2009

River Network Structure: A Template For Understanding Predator-Prey Dynamics And Potential Anthropogenic Impacts, Catherine L. Hein

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A landscape perspective is critically important for understanding community structure, particularly in systems dominated by migratory fauna. I aimed to understand how the structure of riverscapes in Puerto Rico mediates potential anthropogenic impacts, predator-prey interactions, and the migratory behavior of a diadromous species. I surveyed fishes and shrimps at sites throughout two watersheds, designed transplant experiments that investigated the role of natural barriers on predator-prey interactions, and developed models of shrimp migration specific to a particular river network. I did not detect an effect of anthropogenic changes to the landscape on fish and shrimp species distributions in two watersheds that …


Terrestrial Small Mammals From The Gamba Complex In Gabon: Distribution Patterns And Landscape Influences, Carrie J. O'Brien May 2009

Terrestrial Small Mammals From The Gamba Complex In Gabon: Distribution Patterns And Landscape Influences, Carrie J. O'Brien

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The small mammal communities of central Africa are not well understood, and the southwestern section of Gabon has not been previously surveyed except for some recent work in Monts Doudou. At five sites within the Gamba Complex we set out to 1) document the species of terrestrial rodents (Muridae) and shrews (Soricidae) weighing less than 100 g, 2) compare the community composition between inland and coastal sites, and 3) evaluate our sampling protocols. Using a combination of pitfall lines, Sherman live traps, and snap traps we captured 721 individuals of 12 rodent and 10 shrew species in 15,792 trap-nights. The …


Design And Evaluation Of Oligonucleotide Microarrays For The Detection Of Bovine Pathogens, Ryan Weldon Black May 2009

Design And Evaluation Of Oligonucleotide Microarrays For The Detection Of Bovine Pathogens, Ryan Weldon Black

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Two microarray designs were developed and produced to screen for multiple bovine pathogens commonly found in the cattle industry today. The first microarray was designed, built, and processed in-house using conventional material and equipment and targeted Pasteurella multocida, Manheimia haemolytica, Histophilus somni, and Arcanobacterium pyogenes. For each pathogen, 12 perfect-match oligonucleotide probes, which were also designed in-house, targeted different sections of the respective 16S ribosomal genes, and were coupled with 12 corresponding mismatched probes for background. These arrays were able to produce distinct hybridization patterns for each pathogen that were easily visible without the need for …


Linking Space Use And Behavior In Clark's Nutcracker: An Explanation For Seasonal Variation In Space Use, Teresa J. Lorenz May 2009

Linking Space Use And Behavior In Clark's Nutcracker: An Explanation For Seasonal Variation In Space Use, Teresa J. Lorenz

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Clark's Nutcrackers (Nucifraga columbiana) are important seed dispersers for at least 10 species of conifer in western North America and are obligate mutualists for the subalpine tree, whitebark pine (Pinus albicaulis). Despite the important role they play in forest regeneration, space use by nutcrackers has not been formally studied. Several hypotheses exist to explain their year-round space use patterns. I tested one hypothesis that Clark's Nutcrackers migrate altitudinally between summer and autumn in one population in the Cascade Range, Washington. In 2006 and 2007, I compared seasonal differences in summer and autumn space use by 26 …


Validation Of A Peer-Teaching-Peer Paraprofessional Model In Teen Parenting Nutrition Education, Sylvia D. Keller May 2009

Validation Of A Peer-Teaching-Peer Paraprofessional Model In Teen Parenting Nutrition Education, Sylvia D. Keller

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Each year, teen pregnancy occurs in 750,000 15-to-19 year-old women in the United States (U.S.). Utah has the youngest population and the lowest teen abortion rates in the U.S. Approximately 73% of teen pregnancies in Utah result in live births. The prevalence of teen pregnancy and the nutritional risk to mother and child result in a much greater need for social support, such as nutrition education. Current literature shows that the paraprofessional model is effective in increasing positive behavior change through nutrition education. Presently, there is a lack of evidence that paraprofessional teens are capable of accurately and effectively teaching …


Consequences Of Vegetation Change On The Dynamics Of Labile Organic Matter And Soil Nitrogen Cycling In A Semiarid Ecosystem, Toby D. Hooker May 2009

Consequences Of Vegetation Change On The Dynamics Of Labile Organic Matter And Soil Nitrogen Cycling In A Semiarid Ecosystem, Toby D. Hooker

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Sagebrush-dominated ecosystems are being transformed by wildfire, rangeland improvement techniques, and exotic plant invasions. These disturbances have substantial effects on the composition and structure of native vegetation, but the effects on ecosystem C and N dynamics are poorly understood. To examine whether differences in dominant vegetation affect the quantity and quality of plant organic matter inputs to soil, ecosystem C and N pools and rates of plant turnover were compared among historically grazed Wyoming big sagebrush, introduced perennial crested wheatgrass, and invasive annual cheatgrass communities. Since low soil moisture during the summer may inhibit the microbial colonization of plant detrital …


An Investigation Of Postzygotic Reproductive Isolation And Phenotypic Divergence In The Bark Beetle Dendroctonus Ponderosae, Ryan R. Bracewell May 2009

An Investigation Of Postzygotic Reproductive Isolation And Phenotypic Divergence In The Bark Beetle Dendroctonus Ponderosae, Ryan R. Bracewell

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Understanding reproductive isolation and divergence is the focus of speciation research. Recent evidence suggested that some Dendroctonus ponderosae populations produced hybrids with reproductive incompatibilities, a reproductive boundary undetected by phylogeographic analyses using molecular markers. Additionally, the unique bifurcated distribution of D. ponderosae and the proposed isolation-by-distance gene flow pattern around the Great Basin Desert provided a unique opportunity to investigate the evolution of postmating (postyzygotic) isolation while also understanding phenotypic divergence along latitudinal (climatic) gradients. First, I characterized the strength, biological pattern, and geographic pattern of postzygotic isolation in D. ponderosae by crossing increasingly divergent populations in a common garden …


Cognitive Inference And Resulting Behaviors In Response To Ambiguous Threat In The Coyote, Canis Latrans, Sarah Shawnee Dawson May 2009

Cognitive Inference And Resulting Behaviors In Response To Ambiguous Threat In The Coyote, Canis Latrans, Sarah Shawnee Dawson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

While antipredator strategies have been a focus of behavioral research for decades, scientists generally study the responses of prey toward overt, explicit threat. However, risk can also be significant when a threat is covert, such as when an ambush predator may be nearby or a secondary threat remains after a predator's departure. Little is known about the mechanism that prey use to assess risk in a predator's absence. Tests were conducted to determine the manner in which coyotes respond to these ambiguous threats. Specifically, I tested whether coyotes respond to prior anthropogenic activity that has occurred near their only food …


Seed Banks Of Sagebrush Communities Seeded With Crested Wheatgrass, Kevin L. Gunnell May 2009

Seed Banks Of Sagebrush Communities Seeded With Crested Wheatgrass, Kevin L. Gunnell

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Crested wheatgrass (Agropyron cristatum [L.] Gaertn.) is one of the most commonly seeded exotic species in the western United States. Although many degraded Wyoming big sagebrush (Artemisia tridentata ssp. wyomingensis) plant communities have been seeded with crested wheatgrass during rehabilitation efforts, seed banks of these communities have not been characterized. I sought to characterize and explain the variation among 33 seeded communities in the northeastern Great Basin. Hierarchical clustering and principal components analysis identified four possible seed bank categories in these communities. Seed bank categories varied from high to low crested wheatgrass dominance. The crested wheatgrass-dominated category …


Mechanisms Of Induced Cell Death In Bluetongue Virus Challenged Human Cell Lines, Justin Darrel Hoopes May 2009

Mechanisms Of Induced Cell Death In Bluetongue Virus Challenged Human Cell Lines, Justin Darrel Hoopes

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Bluetongue virus (BTV) is a pathogenic member of the Reoviridae family. BTV does not cause disease in humans, but is capable of selectively infecting and killing certain transformed human cell lines. Understanding BTV's oncotrophism may lead to new therapeutics for treating cancer. This study focused on the underlying mechanisms of BTV-induced cell death in carcinoma cell lines. It was our hypothesis that BTV infects human carcinoma transformed cells, produces mRNA and protein, induces a strong inflammatory response, induces mitogen activated protein kinase (MAPK)-based pro-apoptotic signaling, inhibits PKB-based signaling, and eventually kills the cell by inducing apoptosis.

Three carcinoma cell lines …


Effects Of Targeted Grazing And Prescribed Burning On Fire Behavior And Community Dynamics Of A Cheatgrass (Bromus Tectorum)-Dominated Landscape, Joel M. Diamond May 2009

Effects Of Targeted Grazing And Prescribed Burning On Fire Behavior And Community Dynamics Of A Cheatgrass (Bromus Tectorum)-Dominated Landscape, Joel M. Diamond

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Studies were conducted to determine the effectiveness of using targeted grazing and prescribed burning as tools to reduce fire hazards and cheatgrass (Bromus tectorum) dominance on rangelands in the northern Great Basin. A field study, with four grazing-burning treatments (graze and no-burn, graze and burn, no-graze and burn, and no-graze and no-burn), was conducted on a B. tectorum-dominated site near McDermitt, Nevada from 2005-2007. Cattle removed 80-90% of standing biomass in grazed plots in May 2005 and 2006 when B. tectorum was in the boot (phenological) stage. Grazed and ungrazed plots were burned in October 2005 and …


Predicting The Growth Potential Of A Shallow, Warm-Water Sport Fishery: A Spatially Explicit Bioenergetics Approach, Samuel Kirk Dahle May 2009

Predicting The Growth Potential Of A Shallow, Warm-Water Sport Fishery: A Spatially Explicit Bioenergetics Approach, Samuel Kirk Dahle

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Capturing the range of fish consumption and growth potential of large, heterogeneous lentic systems can be challenging due to strong gradients in productivity, the diversity of habits types present, and in some cases, site-specific water quality issues. Cutler Reservoir (Utah, USA) displays a high degree of spatial and temporal variation in physical conditions and potential water quality limitations for fish, including high summertime water temperature and large, diel fluctuations in dissolved oxygen concentrations. The combination of bioenergetics modeling and GIS spatial analysis offers a promising interface for quantifying the fish consumptive and growth potential across a spatially and temporally heterogeneous …


Vegetation Characteristics Of Wyoming Big Sagebrush Communities Historically Seeded With Crested Wheatgrass In Northeastern Great Basin, Usa, Justin Rodney Williams May 2009

Vegetation Characteristics Of Wyoming Big Sagebrush Communities Historically Seeded With Crested Wheatgrass In Northeastern Great Basin, Usa, Justin Rodney Williams

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Crested wheatgrass (Agropyron cristatum [L.] Gaertn.) is one of the most commonly seeded grass species in the western United States and dominates thousands of hectares in the Great Basin. Although many degraded Wyoming big sagebrush (Artemisia tridentata ssp. wyomingensis) plant communities have been seeded with crested wheatgrass, successional pathways, influence of soil attributes, and cultivation history on the vegetation of these communities have not been fully characterized. I sought to identify community phases, vegetative differences, and soil attributes that explain variation among 35 Wyoming big sagebrush communities historically seeded with crested wheatgrass. All communities were more than …